Chain and bucket excavator



w. P HUGHES CHAIN ANDBUCKET "EXQAVATOR Aug. 10 1926.

gwvento'o M ML/AM A flow/Es Patented Aug. 10, 1926.

nra'rsnfsrxras "WILLIAM P. HUGHES, OF ALAMEDA, CALIFORNIA. V

CHAIN AND BUCKET ExcAvA'roR.

Application filed January This invention relates to improvements in chain and bucket excavators, and particularly to the type employed for excavatingland for the recovery of precious metals.

In the operation of excavating land for the recovery of gold or other precious metals by means of an excavator including an endless chain and aline of buckets, the buckets are frequently required to work through muck-or wet earth and this substance, which the action of the buckets operates to com press therein, frequentlyv fails to gravitate from the buckets as these pass around the upper'tumbler of the excavator. The employment of one or more attendants has heretofore been required to efiect dislodgment of the sticky material when the same fails to gravitate freely from the buckets.

The presentinvention has for its'general object the provision of means for automatically scavenging the buckets of a chain and bucket excavator, as the buckets successively pass around the upper tumbler of the excavator.

The above and other objects are accomplished by instrumentalities pointed out in the following-specification.

The invention ,is clearly claims.

A satisfactory embodiment of the invention is illustrated in the accompanying drawings forming part of the specification V and in which- 1 Figure 2, and on the line 3 3 of that figure; and

Figure 4 is a detail plan showing a portion of the upper tumbler and one of the faces thereof.

In the drawings 5 and 6 indicate the upper end portions of the boom. 7 is atransverse shaft having its ends mounted in oppositely disposed bearings in the upper end of the boom and extending through and forming a bearing support for the hub 8 of the upper polygonal tumbler a which is defined in the 28, 1926. Serial No. 84,439.

rigidly secured to the transverse shaft 7. r A centrally disposed radial web 9 formed with hub 8 is peripherally provided with a plurality of angularly disposed yokes 10 which form supports for the links 1313 of the chain and the intervening buckets 15 as these parts move around the tumbler a.

The links 13 of the opposite chains are connected by the usual pintles 14 and are suitably secured as by rivets 16 to the opposite end walls 17 of the buckets 15, all of which is shown in Figures 1 and 2 of the drawings.

The shaft 7 has an axial bore'or passage 18, the outer end of which is connected to shaft and communicating with a port 22 in thehub 8 which extends into a circular chamber 23 in the central portion of the hub. The web is bored transversely at spaced intervals to provide a series of chambers indicated by 24 in Figures 1 and 2. .Each chamber is provided with a valve seat, indicated by 25 in Figure 2, and a valve 26 controls communication between one end portion of the chamber-and a port'27 located in the opposite end of the chamber and extending into the circular chamber 23. 28 in Figures 1 and 2 indicates a series of pockets extending inwardly through the hub from the outer face of the bases 29 of the yokes. The inner. ends of the pockets respectively communicate with the transverse chambers 24. The pockets are provided for the reception of a plurality of hollow cylindrical gaskets 30 which extend beyond the bases 29 of the yokes and through wear plates 31 for the buckets which are secured to the outer faces of the bases 29 in any preferred manner as by screws 32 as indicated in Figure 4.

The straight back plates 33 of the buckets 15 are provided adjacent, their inner sides with relatively small inlet openings 34 which are disposed so as to align substantially axially with the hollow cylindrical gaskets 30, when the buckets are disposed around the tumbler a. The outer ends of the cylindrical gaskets are open as shown in Figures 1 and 2, and the inner ends are provided with ports 35 which approximate in size-the ports 34; and are less than the outer endopenings of the gaskets 30. The. outer end portions of the buckets are counterbored as at 36 soas to. provide shoulders Which form bearing. surfaces for exteriorly disposed collars 37 on tlie .gaskets WVlllGll operate as stops to limit inivard movement of the gaskets. The stems of, valves 23, one of Which is shown in Figure 2 and indicated by. 38, areqadapted, to be operated to re oipfroca-te passingiipon and. overa cam 39, herein shown as ,being formed. With a the inner face .and ;upper end portion of .the side 6 of the. Lboomythe cam extendingfor- Wardly and downwardly, as shown :in Figures, 2; :and' 3.. Each of the stemsj38 extends through aguide a0 secured to one-lace of Web: 9, theouter end of the stern beingprovided. ith a roller 41 Which-rides upon ,the cam 39 in the rotation of the upper tumbler a. "I Compression springs,;.one of Whichis show-n air-Figure 2.;and indicated by 4 2, are disposed between the valve seatsi2'5 of the valves, 26 and the inner @ends of the-guides 40, a pin 4:3, or its equivalent; being secured toxeach .valve ,stem. and operating to-conupress. the 'springwhen Lthe stemlis moved. in- Wardly in the opening of-the valve and during the time'the roller :41 is passing over the cam 39...] i

" In the operation. of Jihakiviba, thoseio f the valves 26. WllOSG rollers 41 are'out of Contact .W:ith-*tl1e..cam- 39,. are seated Within the .seats 25 so that communication. between the transverseichambers 24 and the. annular chamber. 23 -is interrupted. .Waterunde r pressure is at all.;times..With-in the :Water supply :pipe, 19.1.andv within..-.the annular chamber 23, :so .thataintheturning .of'zthe upper tumbler and Whenuthe :roller of lone of. the valve stems, moves in-to. contact withzthe cam-39and causes the valve .26 thereof to moveto the positiongsho-vin in Figure 2, Water flows from...ia1inular.,chani ber 23 through port 27 and intotra'nsverse chamber 24L and then through port 25 and through gasketv 26 and'inlet passage 34 and into 011601? the buckets. 15;. The caml39is so disposed land proportioned-as :to. effect the operation of a valvleat thetime that a bucket'passes the l1igli point of. the boom and begins to descend. and occupy thelower run of the bucket chain. The lengthofthe cam, is suchias'tohold the valve of the said bucket open until such time. as;the :position ofithebucket is coinpletely inverted. It is obvious that the Water.underflpressure entering the bucket through the :inlet zpass'a'ge 34-operates to deta'ch'theearththat adheres tolthe. inner -surface of the bucketandto liquefylthe earthy contents of the bucket to a great extent, so that When the bucket moves into:a substantialy inverted'position, the discharge of its contents is provided for not only by the action of the Waterfloyving contents ofhthe bucket.

movesbeyond cam 39, spring 4:2 operates to ,close the valve 26 whereupon the Water supply to-th'e'bucket iscut off. At about this into the .bucket,;;but by .the weightof the When the bucket v time succeeding upwardly moving bucket 'is in 'posltion'to beoperated upon by cam 39 and; to have.its contents opera-ted upon by Water as described forthe first menti-oned:bucket. f .i

It will .be notedthat inletpassage 34 of each bucket is considerably smalleir than-the outer ends offlgaskets i35n This [is to. P110 vide Ifor alin'ernent at all times between the ports ofthe buckets and. the;gaskets, re-. gardless oflthe usual slight ZLIIlOllIlhmOf lateral displacement ,that, is invariably h-ad on theipart ofthejbuckets in. moving around the upper tumbler. Thegprovisionaotthe relatively vvsmall -inlet,p.o1ts. 35 at the inner ends of the gaskets provides forvpbtaining suiiic'ient pressure on? the] inner ;ei1dsf of. the gasket-s so as toflinsurefla tendency on, the

into tight contact with :the backdplatef 3350f the buckets, andfthereby Epfrevent leakage and lossofpressure onthe par'tof thewa 7 ter--.in,-passingv into the.;b,uckets 'Although [I have shownlfand described 7 one. embodimentwofvmy invention, ,it is to be understood that the same issusceptible ofvarious changes; and I reserve fthe right to employ such as may come within the scope .of-the appended {claims-,-

jlclaim; q 7 1. In a chain andbuc'ket: excavato1 ;'a,support, a tumbler shaft carriedhy; the support and having-an open-ended fluid passage, one end of which is adaptedtojbe; connected to a .fluid supply pipe, a {polygonal tumbler carried by the shaft and having-72a plurality of Water 1 passages extendinggoutwardly from the. water ipa'ssage of the shatt and opening through the side V faces, of Zthejtumbler, an. endless :buck'etiline including a-plm .rality. of bucketstra-ined aroundthetumbler and having b'ackportions provided with inlet openings disposed so as;to. .i egister with the outer ends of the Water ;passages =of athe tumbler as :the;buckets;move around {the 5 tumbler, zvalves-qdisposed in the wgater passages of the tumbler for; controlling, the, passageof ,Wjater therefrom to the buckets; "and means-connected to the support ;for gperating the valves" to 0 en successively infthe turning-ofthetumb er.,; n a l ,2. Ina-chain and ibucketexcavato-r, a support, a tumbler-shaft carried by the sup port. and. having, an; open;ended fluid ;p as sage,onelfend of hichisj adapted tOjbQfiQIb nected to. -a;fluid supply .-pipe,ia polygonal tumbler carried by the shaft Kandjhaving a plurality of. Waterepassages, extending nut- Wardly fromthe water: passage,of the shaft and opening through the side faces-of the tumbler, an endless bucket line including a plurality of buckets trained around the tumbler and having back portions provided with inlet openings disposed so as to register with the outer ends of the water passages of the tumbler as the buckets move around the tumbler, selfclosing valves disposed in the water passages of the tumbler for controlling the passage of water therefrom to the buckets, said valves having valve stems extending laterally outward from the tumbler, and means connected to the support for operating the valve stems successively to open the valves in the turning of the tumblers.

3. In av chain and bucket excavator, a support, a tumbler shaft carried by the support and having-an open-ended fluid passage, one end of which is adapted to be connected to a fluid supply pipe, a polygonal tumbler carried by the shaft and having a plurality of water passages extending outwardly from the water passage of the shaft and opening through the side faces of.

the tumbler, an endless bucket line includ-' ing a plurality of buckets trained around the tumbler and having back portions provided with inlet openings disposed so as to register with the outer ends of the water passages of the tumbler as the buckets move around the tumbler, valves disposed in the water passages of the tumbler for controlling the passage of Water therefrom to the buckets, means connected to the support for operating the valves to open successively in the turning of the tumbler, gasket members disposed in the outer end portions of the fluid passages of the tumbler and responsive to fluid pressure in the said passages and adapted to move outwardly and into contact with the buckets when the valves are opened.

WILLIAM P. HUGHES. 

